Nov 20 (Reuters) - A U.S. court has denied a request by Indian drugmaker Ranbaxy Laboratories Ltd to stop competitors from launching copies of AstraZeneca Plc’s heartburn pill Nexium and Roche’s antiviral, a court filing showed.

Ranbaxy had filed a lawsuit against the U.S. Food and Drug Administration last week for revoking tentative approvals it gave the company to make generics of Valcyte and Nexium.

Ranbaxy had also sought to prevent Endo International Plc and Dr Reddy’s Laboratories from making the generics after the FDA gave the two companies approvals to launch their own copies.

Endo said on Thursday it launched its generic version of Valcyte, prescribed to treat a type of viral infection in AIDS patients.

A spokeswoman for Dr Reddy’s said the company would launch its own generic version of Valcyte “shortly”, but declined from being more specific.

U.S. District Judge Beryl Howell in Minneapolis denied Ranbaxy’s request, the court filing showed. The company, which is being acquired by larger local rival Sun Pharmaceutical Industries Ltd for $3.2 billion, declined to comment on the case.

Valcyte had total U.S. sales of about $440 million in the 12 months ending Sept. 30, Endo said, citing IMS Health data.

A generic version of Valcyte could add between $35 million and $40 million to Endo’s annual revenue, Guggenheim Securities said in a note earlier this month.

Analysts had expected generic Nexium to add about $150 million to Ranbaxy’s overall sales in the first six months after its launch, while generic Valcyte was seen adding about $50 million.

Earlier this month, the FDA told Ranbaxy it had made an error in granting the company tentative approval to launch the drugs, citing manufacturing quality lapses at Ranbaxy’s India plants.

Ranbaxy and the FDA have until Nov. 21 to submit a schedule for further proceedings in the case, the court filing showed.

Ranbaxy shares closed up 3.5 percent at 623.45 rupees on Thursday. Endo shares were up 0.4 percent at $69.31 in early trading on the Nasdaq on Thursday. (Reporting by Zeba Siddiqui in Mumbai, Joseph Ax in New York and Amrutha Penumudi in Bangalore; Editing by Miral Fahmy and Savio D‘Souza)